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New requirements placed to products, and hence to materials from which they are produced resulted in widespread use of instruments of quality assurance. Depending on destination of the product, its manufacturing process is burdened with the need to implement quality assurance systems, recording and analysing data, and also a process of continuous improvement. The article presents the results of practical use of selected quality tools in iron foundry. In order to determine the level of incompatibility of manufactured products the analysis was carried out based on the use of Ishikawa diagram and Pareto-Lorenz method. The results of the above analysis were defined as a starting point to develop a dendrogram and to determine the variant solution to the problem using programming of decision-making process, there was also developed diagram of the manufacturing process of iron castings.

Grinding is the most common finishing process for components that require high accuracy and surface quality. Process performance depends on many factors related to process conditions, workpiece material, grinding fluid but grinding wheel is of special interest. Grinding wheel performance plays a major role on workpiece quality and process efficiency; preparation of the grinding tools and the creation of specific topography of the wheel surface is in direct relation to grinding wheel performance. Questions connected to the possibility to increase production efficiency of diamond dressers owing to technological changes of their production and simplification of preliminary selection of initial samples of diamond are considered. Furthermore, recommendations on improvement of the dressing process of abrasive wheels are made using 3D FEM simulations. The results of theoretical and experimental investigations which cover the development and research on electrochemical dressing of working surface of diamond grinding wheels with metal bonds are also provided.

The present article is focused on the non-destructive testing (NDT) inspection of pipelines during operation namely Magnetic Flux Leakage (MFL) method and Phased Array ultrasonic (PA) method. MFL inspection technique is electromagnetic test method primarily used to detect flaws or defects in high-permeability of ferromagnetic metals such as carbon steel tubing, plate, wire rope and tubular parts. PA ultrasonic method is an advanced NDT method that is used to detect component failures i.e. cracks or flaws and thereby determine component quality. Due to the possibility to control parameters such as beam angle and focal distance, this method is very efficient regarding to the defect detection and speed of testing. In this article real pipeline defect was identified by MFL method in the internal pipe inspection. This defect was fully mapped by Phased Array ultrasonic method in the terrain. 3D model of defect in the tested material was created from measured data and obtained by PA method. The real dimensions of the defect determined from measurements by the method of MFL and PA are compared.

Polymeric materials are used in modern medicine for the fixation of fractured bones. Their function is only temporary - they serve as substitutes till they are replaced by human tissue (without additional reoperation). Their disadvantage is that they possess low mechanical strength and hardness. As an alternative to polymeric materials, the metallic fixation components are being developed. Their advantage is the higher value of strength, toughness and hardness. Zinc alloys represent a new trend in this technological field. They also meet the requirements for biocompatibility and their mechanical properties approach the properties of human bones. In this paper, the structural and mechanical characteristics are described. The only alloying element in the zinc alloys examined was magnesium in the range 0-8.3 wt. %. The mechanical properties were discussed in the relation to the microstructure and the phase composition of the alloys. The results showed that the mechanical properties of binary Zn-Mg alloys increase with the growing content of Mg with the maximum achieved at the eutectic composition. Higher magnesium content strongly deteriorates the mechanical properties of these alloys.

Most of magnesium alloys are usually used for applications at ambient temperature. The significant decrease in mechanical properties is observed already at the temperatures higher than 150°C. This is the reason for the effort to prepare a new low-priced magnesium based alloys with improved mechanical properties at elevated temperatures, e.g. for components of combustion engines. The microstructure and mechanical properties of selected commercial magnesium alloys AZ31, EZ23, ZE41 and WE43 with relatively new MRI153 alloy for use at elevat-ed temperature were compared. Brinell hardness, yield strength and tensile strength at the temperatures of 20, 150 and 200°C were studied. It was found, that relatively low-priced MRI153 alloy appears to be very good alternative alloy for use at elevated temperatures.

Modifying of alloys is an important part of the metallurgical process and involves the course also of alloys of aluminum, specifically the Al-Si (silumin) in our case. One of the elements that it is possible used to modify for type of alloy Al-Si is antimony (Sb). This paper investigates potential impact of the modification of this element for AlSi7Mg0.3 alloy on tool wear in cutting process. Within experiments were made three casts of master alloy AlSi7Mg0.3 without additional modification and three casts from this ligatures that were more subsequently modified by 0.05 wt% Sb on the cast. These castings were then machined to the same cutting conditions and was assessed the resulting wear of inserts. The present experiment and analysis are part of larger research that are carried out at the Faculty of Production Technology and Management of Jan Evangelista Purkyně University in Ústí nad Labem.

This article focuses on an analysis and a transfer process of CT clinical metadata of a real patient gained within a cooperation, research and development of an individual knee joint implant at Clinique of Display Methods in Saint Anna's Teaching hospital in Brno. The first part of the article is aimed at the application of a software 3D-DOCTOR that enables gaining of demanded output data (e.g. a model of patient bone part, i.e. knee joints) from scanned input CT metadata in DICOM format (Digital Imaging and Communications in Medicine). The output data are gained in format *.stl (Stereo Lithography) to further possible usage (e.g. a design and a production of individual total joint prosthesis). The second part of the article concentrates on an application of software RP MiniMagics that enables editing, modification and the whole optimization of polygon net by which models of distal part of femur and proximal part of tibia are described.

This paper deals with non destructive magnetic evaluation of ground surfaces of variable hardness based on Barkhausen noise (BN) technique. Except magnetic investigation, obtained BN signals are correlated with metallographic observation, microhardness readings as well as residual stress measurements. The results show that regime of heat treatment - annealing after hardening significantly affects the possible concept for monitoring surfaces after grinding. Conventionally heat treated surfaces of hardness 62 HRC indicate the typical surface thermal softening induced by grinding cycle whereas samples of lower hardness exhibit rehardening effect associated with the progressive decrease of Barkhausen noise responses along with the developed grinding wheel wear.

Material crystal compositions and their phase structures have become the necessary and important part of the materials research and advanced technology in recent decades. Each property and information about material phase structure is more or less immediate way depending on the structure and crystal composition. Prerequisite of any technological breakthroughs in this area is therefore detailed information on the structural parameters of materials.

Magnesium alloys are progressive light-weight materials with a great potential in automotive and aerospace applications in which they enable significant weight and fuel savings. However, the main drawback of the most widely used AZ type magnesium alloys (Mg-Al-Zn) is a very poor thermal stability. The AZ alloys cannot be applied in components exposed to temperatures exceeding 120°C, because of a rapid drop of mechanical characteristics at above this temperature. There are two approaches to improve the thermal stability of Mg alloys. The first one consists in alloying with rare earth metals and the second one involves simoultaneous additives of aluminium and alkaline earth metals (Ca, Sr). In the present study, microstructures, mechanical properties and thermal stability are characterized for advanced commercial Mg alloys, WE43 (MgY4Nd2RE1Zr) and AJ62 (MgAl6Sr2) developed for elevated temperature applications. It is semonstrated that thermal stability of both kinds of alloys significantly exceeds that of the commercial casting AZ91 (MgAl9Zn1) alloy.

Precise characterization of surface topography is very important in many engineering industries. This paper describes potential possibilities of using optical 3D (three dimensional) measurement methods in surface metrology. Surface integrity describes the status and attributes of the machined surface. This paper presents possibilities of using and measurements of surface integrity, namely the surface topography and the physical parameters of which are analysis of microstructure and microhardness of the surface layer.

Computer tomography could be used for non-destructive inspection of castings. This contribution deals with application of computer tomography for determination of inner quality of high-pressure die casting parts, especially in relation to leakage and compared with other testing methods. In praxis, the leakage location is identified by fracture test or by metallographic observation. Often the oxides and porosity are found. Porosity is also often found out after machining operations. This work proposes non-destructive methods of castings inspection, especially tomography, in comparison of other known and available methods, with the goal to find out the problem before machining with minimal losses.

This article describes the principle of Green Machining technologies and experimental tracking of moisture of ceramic granulate during the drying process. Green machining involves the machining of metal or ceramic bodies in the "green" state prior to sintering. Typically these bodies are comprised of ceramic or metal powder held together by an organic binder. In this state they are far easier to machine than monolithic blocks of the corresponding metal and ceramic. One of the materials that can be used in the green machining is silicon carbide. This material is produced in the process of spraying the emulsion in drying kiln. This process is very important considering the quality of ceramic powder with respect to its further use. One of the most important parameters to be monitored during the spraying is the moisture of the ceramic powder (granulate). [8][2]

Metal foams belong thanks to their unique properties into the group of new and perspective materials. The paper deals with foundry procedures used for production of cast metal foams based on non-ferrous metals alloys. Individual procedures of production in lab and pilot conditions are described, which result in casting with certain structural regularity. Attention is paid also to the obtained microstructure of these cast materials and to evaluation of their properties. The experimental part summarises the existing research works in this area, including future possibilities of their use. Cast metal foams are not yet produced in Czech Republic on industrial scale.

Nanocrystalline metals are advanced materials with structural constituents smaller than 100 nm. With respect to structure, they are characterized by high strength and hardness, gas absorption capability, high specific surface area, catalytic activity or magnetic properties. These properties predispose them for using in wide spectrum of possible applications, namely advanced structural and functional applications, biomedicine, catalysis or electronics. Many methods have been developed for producing nanocrystalline metals or nanocrystalline metallic powders including precipitation from supersaturated liquids, severe plastic deformation, cryo-melting, or inert gas condensation. In this work, another promising method - selective dissolving of aluminium alloy was successfully appliedfor preparation of nanocrystalline copper powder and this powder was consequently used for producing of bulk nanocrystalline material with enhanced hardness and strength.

The determination of the ploughing forces is necessary for wear monitoring of the cutting tool in micro cutting. The extrapolation method on zero cut chip thickness is used very often to determine the ploughing forces. But there are many opponents of the extrapolation method on zero uncut thickness. The aim of this research was to increase the accuracy of determination of the ploughing force and to investigate the effect of processing materials and cutting tool wear on the ploughing force values. To achieve this aim was used the method comparing total forces at different flank levels of wear to determine the ploughing forces. The experiments were performed by cutting of aluminum alloys, structural steels and stainless steel with different cutting tool wear.

This work deals with modification of aluminum alloy AlSi6Cu4 with strontium in graduated amounts. Submited article examines modification influence on the mechanical properties such as tensile strength (Rm), elongation (A5) and Brinell hardness (HBW). Article also includes analysis of alloy microstructure modified by strontium and analyzes the impact of strontium on the gas content of the melt. This work deals with finding the optimal amount of strontium to achieve changes in the shape of the coarse eutectic silicon plates to fine rounded AlSi6Cu4 alloy rods. Durin experiment was found, that optimum amount of the used modifier with respect to the mechanical properties of the surveyed sample is 2000 ppm AlSr5. But with the increasing amount of modifier in the alloy decreases fludity.

The article deals with the influence of charge composition on the microstructure and mechanical properties of synthetic nodular cast irons after casting and after heat treatment (ferritizing annealing and isothermal heat treatment). The paper shows a comparison of the microstructure of nodular cast irons with the graded amount of steel scrap in a charge. The chemical composition of individual meltages was regulated alternatively by ferrosilicon (FeSi) and carburizer or metallurgical silicon carbide (SiC). The results of the experiments show that the SiC additive positively influences the microstructure as well as the mechanical properties of nodular cast iron, especially in specimens from the meltages with a higher ratio of steel scrap in the charge. Moreover, the production of synthetic nodular cast irons with a SiC additive is economically advantageous.

Projecting and designing of automated assembly cells/lines is very complicated process. The rising demand on an assembly high quality, precision, effectiveness and shorter time to market. Puts the high requirements on the all active devices which act at the automated workplace. Assembly robot with its effector influences the effectiveness of the proposed assembly automation very significantly. Design or choice of the assembly robot and its robotic gripper namely is very important step of the automated assembly cells/lines projecting. Secure and stable holding of an assembly object by robotic gripper is one of significant conditions for trouble-less execution of the object automatic implementation into assembly joint. This article presents our experiences with utilization of advanced simulation methods for the specialized robotic gripper grasping ability exploration for purposes to evaluate a safe and stable grasping of different objects. Virtual reality tools - eon reality and haptic device with glove and finger actuators (CyberForce) were applied for simulation experiments realization too.

Polyurethanes belong to a wide group of polymers which are applied in many industrial branches. Some polyurethanes can be filled with various types of fillers which optimize their properties for given application. In the paper there are described basic mechanical properties of a constructional two-component polyurethane resin which was filled with microparticles of a glass powder. The aim of the experiment is to define a resulted hardness, a tensile strength and a shear strength of the filled polyurethane resin and set its utility properties further to an application usage of a company PSP Izoterm Ltd. From the measured values 14% increase of the hardness of the filled systems compared with the unfilled resin is visible, the shear strength of the filled systems did not differ statistically significantly from the unfilled polyurethane, the tensile strength of the polyurethane filled with 5% of the glass powder was statistically the same with the strength of the unfilled polyurethane.

Porous alloys are very perspective materials for medical implants, particularly for surgical and dental applications. The reason - besides their biocompatibility - is their density. This is why the implants and bone replacements are lighter and more similar to a human bone in its structure and mechanical properties. Another advantage is good osseointegration, i.e. tissue growing through pores in the material, this makes the body accept the implant better and there is also no risk of rejection. New Ti-Si biomaterials were prepared by powder metallurgy using reactive sintering, during which the desired porous structure of the material is formed. In this experiment the observed subject was the microstructure of Ti-Si alloys, properties determined were porosity and yield strength in compression.

Technical literature presents numerous experiments with rotary turning tools application. Their advantages include extremely high durability, better quality of the machined surface as well as good chip shaping. Their wider industrial utilization was prevented due to the fact that a bearing is extremely dynamically stressed by a cutting force. Antifriction bearings have to big sizes and cause oscillation in the system, while sliding bearings manifested short durability and slackness inside. The authors of the paper tried to solve the mentioned problem by the application of an adjustable tapered roller bearing, ensuring a stable machining process. The paper contains the design as well as the results of the experimental verification obtained by the application of this improved tool.

This article presents the metallurgical and material properties of castings from stainless steel G-X4CrNi13-4 and G-X4CrNiCu13-4, which can be obtained under the conditions of the Foundry shop of PILSEN STEEL s.r.o. The article mentions furnace units of primary and secondary metallurgy in which the stated quality steel is produced. By way of illustration of achieved properties of melt, the heat analyses and micro-purity of steel are shown. Mechanical properties of steel are represented in well arranged graphs showing achieved values of the yield point, tensile strength, and impact energy at various temperatures, such as for example: 20, -10, -20, -30, -40, -50 a -60°C. By way of illustration, there are figures of the castings most frequently produced from stainless steel in the Foundry shop of PILSEN STEEL s.r.o. In the end, the article points out what effect has micro-purity of steel on the value of impact energy.

The aim of the article is to present the necessity of completion of the test stand of brake components of railway vehicles with the equivalent railway operation load simulator for the research of the wheel wear on it. The other aim of presented research needs is to perform the analysis of the equivalent conicity as a parameter for the rail vehicles in operation ride properties prediction. The sub aims are the change of frame, wheel, braking forces load via SIMRAIL simulator program load collection performance.

This paper presents results of study of grinded gears in order to describes surface integrity and verify the correlation between Barkhausen noise analysis and X-ray diffraction. Gears are used in the wind power plant and made of case-hardened steel 18CrNiMo7-6. Barkhausen noise analysis and X-ray diffraction was used for measurement. Barkhausen analysis method is one of the fast nondestructive methods used to assess the integrity of surface. For comparison of grinding processes were used different cutting speeds and numbers of material removal. X-ray diffraction method was used also for measurement of residual stresses. Due to correlation between measured values the optimization of grinding process of gears will be done.

The main goal of the research presented in this paper is to gain a deeper understanding of solidification processes in terms of porosity formation in AlSi7Cu0.5Mg alloy through complex data evaluation obtained from thermal analysis, simulation software ProCAST and also from real melts. Formation of porosity (micro, macro porosity) was examined under different casting conditions, the pouring temperature varied from 730 °C to 650 °C. The experiment will attempt to analyze, how the pouring temperature effects the formation and character of porosity. For this purpose was various methods were used, not only real castings evaluation, but also advanced porosity module integrated into simulation software ProCAST. Experiments also try to compare simulation results with real conditions, to determine software abilities and accuracy. Specific casting and mold were designed to be able to observe porosity formation.

This investigates influence of non-conventional methods of parting of steel 11 373.0 on structure transformations and associated geometry. Wire electro discharge machining (WEDM), plasma and laser cutting methods were used and compared as competitive methods from the point of view of structure transformations, associated geometry of a part and associated cutting forced produced during the following milling process. Results of this study indicate that significant differences can be found among the mentioned technology since the different thermal load of machined surface. Furthermore, structure and geometry alteration occurring after parting strongly affect cutting forces during the following milling operations.

The solidification process of a metal or alloy is accompanied by the evolution of heat the magnitude of which depends on the various phases that form during the solidification. Recorded temperature-time data can yield quantitative information about the alloy solidification process. Such a plot is called a cooling curve and the general name given to the technique is thermal analysis. The cooling curve serves as a "finger print" of the solidification process and can be used to predict the structure of the test sample and consequently the actual casting. The aim of this paper is to show the ability of the thermal analysis technique in order to predict some of the key solidification parameters, which can be used to monitor and improve the quality of the casting. In addition, some of the results collected from the cooling curve can be used as an input data in existing software packages in order to improve their accuracy.

ŠKODA VÝZKUM s.r.o. (now Výzkumný a zkušební ústav Plzeň s.r.o.) cooperated on the development of the NEOPLAN DMA low-floor articulated trolleybus intended for the Boston city (the United States). Multibody models and finite element models of the trolleybus were utilized in the stage of the vehicle design. The multibody models of the trolleybus were created in the Alaska simulation tool and the simulations (running over a large road unevenness, start, braking and driving through a bend) were aimed at determining forces acting in the trolleybus suspension elements and radius rods. Time histories of the forces calculated using multibody models were used as the input data of the trolleybus finite element models. Utilizing the finite element models the critical places of the trolleybus body structure from the point of view of high stresses were determined. At the measurement with the real trolleybus prototype these places were provided with strain gauges.